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Showing papers on "Xanthone published in 1997"


Journal ArticleDOI
TL;DR: A xanthone derivative, subelliptenone F, and related compounds showed an intensive inhibitory effect against topoisomerases I and II in in vitro experiments as mentioned in this paper.
Abstract: A xanthone derivative, subelliptenone F, and the related compounds showed an intensive inhibitory effect against topoisomerases I and II in in vitro experiments. These xanthones are prospective lead compounds for anticancer drugs.

59 citations


Journal ArticleDOI
TL;DR: In this article, a depsidone named garcinisidone-A (1), six new xanthones named assiguxanthone-a (3), -B (9), -C (15), and -D (16), as well as some known xanthone, benzophenone, chromone, and biflavanone derivatives, and their structures were elucidated by spectroscopic methods.
Abstract: Constituents of three EtOH extracts of the stem bark of Garcinia assigu LANTB., Garcinia dulcis (ROXB.) KURZ., and Garcinia latissima MIQ., belonging to the Guttiferae, collected in Central Province of Papua New Guinea, were studied. A novel depsidone named garcinisidone-A (1), six new xanthones named assiguxanthone-A (3) and -B (9) and dulxanthone-A (4), -B (6), -C (7), and - D (11), and four new pyranoxanthones named latisxanthone-A (13), -B (14), -C (15), and -D (16) were isolated, as well as some known xanthone, benzophenone, chromone, and biflavanone derivatives, and their structures were elucidated by spectroscopic methods. Among these components, garcinisidone-A (1) is the first example of a depsidone derivative having a five-carbon unit (prenyl) as a substituent to be found in nature. Latisxanthone-B (14) was found to contain a hydroperoxy moiety in the molecule. This is the second example of a xanthone hydroperoxide to be found in nature.

57 citations


Journal ArticleDOI
02 Dec 1997-Planta
TL;DR: In this article, a regioselective cyclization of an intermediate benzophenone to a xanthone was shown to depend on cytochrome P450, as shown by the effectiveness of established P450 inhibitors.
Abstract: A crucial step in plant xanthone biosynthesis is the cyclization of an intermediate benzophenone to a xanthone In cultured cells of Centaurium erythraea RAFN, 2,3′,4,6-tetrahydroxybenzophenone (THBP) was shown to be intramolecularly coupled to 1,3,5-trihydroxyxanthone, whereas in cell cultures of Hypericum androsaemum L it was coupled to form the isomeric 1,3,7-trihydroxyxanthone These regioselective cyclizations that occur ortho and para, respectively, to the 3′-hydroxy group of the benzophenone depend on cytochrome P450, as shown by the effectiveness of established P450 inhibitors and blue-light-reversible carbon monoxide inhibition Furthermore, the reactions absolutely require NADPH and O2 The underlying reaction mechanism is probably an oxidative phenol coupling that is catalyzed regioselectively by xanthone synthases These enzymes are proposed to be cytochrome P450 oxidases The intramolecular cyclizations of THBP to 1,3,5- and 1,3,7-trihydroxyxanthones catalyzed by the two xanthone synthases represent an important branch point in the plant xanthone biosynthetic pathway

54 citations


Journal ArticleDOI
TL;DR: In this article, apetalinone A-C and tomentonone were isolated from the roots of Calophyllum apetalum, which indicated a new biosynthetic pathway including Claisen rearrangement and Diels-Alder reaction.

32 citations


Journal ArticleDOI
TL;DR: As a broad-spectrum antifungal agent, Sch 54445 exhibits highly potent activities against various yeasts and dermatophytes with MIC values approximately 0.00038 microgram/mL.
Abstract: A novel antifungal agent, Sch 54445, was isolated from the fermentation broth of an Actinoplanes species. Sch 54445 was identified as a polycyclic xanthone related to the albofungin family of compounds on the basis of analyses of spectroscopic data. As a broad-spectrum antifungal agent, Sch 54445 exhibits highly potent activities against various yeasts and dermatophytes with MIC values approximately 0.00038 microgram/mL.

31 citations


Journal ArticleDOI
TL;DR: The stem bark of Garcinia cowa furnished a new xanthone which was characterized as 7-O -methyl-garcinone E. as mentioned in this paper, which was used in the development of a new Xanthone Identification System.

30 citations


Journal ArticleDOI
TL;DR: Xanthone concentration dependently inhibited the 45Ca2+ influx induced by either norepinephrine or high-K+, suggesting that xanthone might act as a blocker of both receptor-operated and voltage-dependent Ca2+ channels.

30 citations


Journal ArticleDOI
TL;DR: A new xanthone named demethylpaxanthonin, 1,2,5,6,tetrahydroxy-2-2′,2′-dimethyl-4′-isopropenyl)-cyclopentanyl-xanthen-9-one, has been isolated from the callus tissues of Hypericum patulum together with the known compounds padiaxanthone and tripteroide.

29 citations


Patent
20 Mar 1997
TL;DR: In this article, therapeutic compositions for the treatment of infectious diseases are disclosed, which include xanthones and xanthone derivatives, such as 2,3,4,5,6-pentahydroxyxanthone.
Abstract: Therapeutic compositions for the treatment of infectious diseases are disclosed. These compositions comprise xanthones and xanthone derivatives, such as 2,3,4,5,6-pentahydroxyxanthone. Also disclosed are methods for the treatment of infectious diseases using such compounds.

26 citations


Journal ArticleDOI
TL;DR: In this article, a new synthetic approach to angularly-fused and simpler substituted xanthones is described based upon the benzannulation of 2-(o-anisoyl)-4-hetero-aryl-2-cyclobutenones and 2-(2-(1,3-dithian)-2-yl)-4alkenyl-2.

22 citations


Journal ArticleDOI
TL;DR: From the aerial parts of Mammea acuminata, a new xanthone was isolated in addition to two known xanthones (1,5-dihydroxy- and 5-hydroxy-1-methoxyxanthone) and (−)-epicatechin.

Patent
09 May 1997
TL;DR: In this article, the problem of obtaining the subject inhibitor having testosterone-5-reductase inhibiting action and useful as a preventive and/or therapeutic agent of depilation, acne, prostatomegbly, prostatic cancer, etc., by including a specific xanthone or its salt as an active ingredient was addressed.
Abstract: PROBLEM TO BE SOLVED: To obtain the subject inhibitor having testosterone-5-reductase inhibiting action and useful as a preventive and/or therapeutic agent of depilation, acne, prostatomegbly, prostatic cancer, etc., by including a specific xanthone or its salt as an active ingredient. SOLUTION: This inhibitor contains a xanthone derivative represented by the formula (R1 to R8 is H, an alkyl, an alkenyl, an alkoxy or the like), e.g. 1,3,6-trihydroxy-7-methoxy-2,8-bis-(3-methyl-2-butenyl)xanthine-9-one( α-mangosteen) or its salt as an active ingredient. Furthermore, it is preferable that the above derivative is one or two or more kinds of extracts of each higher plant belonging to the family Guttiferae, Gentianaceae, Moraceae, Polygalaceae or Liliaceae and each lichen or fungus of the family Parmeloaceae, Pertusariaceae, Aspergillaceae or Clavicipitaceae and the xanthone derivative is preferably formulated in an amount of 0.0001-20 wt.%.

Journal Article
TL;DR: Xilingzhimu, the rhizomes of Anemarrhena asphodeloides Bunge (Liliaceae), has been prescribed as antipyretic, anti-inflammatory, diuretic and hypoglycemic agents in Chinese traditional medicine as discussed by the authors.
Abstract: Xilingzhimu, the rhizomes of Anemarrhena asphodeloides Bunge (Liliaceae), has been prescribed as antipyretic, anti-inflammatory, diuretic and hypoglycemic agents in Chinese traditional medicine. In this paper, two xanthone glycosides I and II, were isolated from Xilingzhimu by conventional method. The structures of I and II were identified on the basis of chemical reactions and UV, IR, 1HNMR, 13CNMR and DEPT. Compound I was identified as mangiferin and II is a new compound, named neomangiferin. Its structure is 7-O-beta-D-glucopyranosyl-mangiferin.

Journal ArticleDOI
TL;DR: In a search for inhibitors of platelet aggregation, a number of α-methylidene-γ-butyrolactones 5 and 6 bearing flavone or xanthone moieties were synthesized and evaluated for their antiplatelet activity against thrombin(Thr)-, arachidonic-acid(AA), collagen(Col)−, and platelet-activating-factor(PAF)-induced aggregation in washed rabbit platelets.
Abstract: In a search for inhibitors of platelet aggregation, a number of α-methylidene-γ-butyrolactones 5 and 6 bearing flavone or xanthone moieties, respectively, were synthesized and evaluated for their antiplatelet activity against thrombin(Thr)-, arachidonic-acid(AA)-, collagen(Col)−, and platelet-activating-factor(PAF)-induced aggregation in washed rabbit platelets. These compounds were synthesized from 7-hydroxyflavone (1) or 3-hydroxyxanthone (2) via O-alkylation ( 3 and 4, resp.) and Reformatsky-type condensation (Scheme). Most of the flavone-containing α-methylidene-γ-butyrolactones 5a–d showed potent antiplatelet effects on AA- and Col-induced aggregation, while xanthone derivatives 6c–e were found to have the same pharmacological profile than aspirin in which only AA-induced aggregation was inhibited (Table 1). However, 6c–e were approximately three to ten times more potent than aspirin (Table 2). For the vasorelaxing effects, 5a was the only compound which exhibited significant inhibitory activity on the high-K+ medium, Ca2+-induced vasoconstriction (Table3). Both 5a and 6a, with an aliphatic Me substituent at C(γ) of the lactone, were active against norepinephrine-induced phasic and tonic constrictions while their γ-aryl-substituted counterparts 5b–f and 6b–f were inactive.

Journal ArticleDOI
TL;DR: In this article, reaction of dienamine with dimethyl acetylenedicarboxylate and dimethyl maleimide was shown to yield xanthone and chromone, respectively.
Abstract: Reaction of dienamine 2 (R = H and Me) with N -phenylmaleimide or chromone 3 gives xanthones 5 and 8, respectively, through initial [4 + 2] cycloaddition, whereas reaction with dimethyl acetylenedicarboxylate affords xanthone 13.

Journal ArticleDOI
TL;DR: This communication describes fermentation, isolation, structure elucidation and antitumor activities of F390B, C and nidulalin A in Penicillium sp.
Abstract: shown in Fig. 1). In this communication, we describe fermentation, isolation, structure elucidation and antitumor activities of F390B, C and nidulalin A. Culture, AJ117292, was isolated from a soil sample collected at KanagawaPrefecture, Japan and the fungus, AJ117291 was isolated from a soil sample collected at Ehime Prefecture, Japan. Both of the strains were identified as Penicillium sp. by morphological characteristics, and AJ117292 was deposited at the National

Journal ArticleDOI
TL;DR: In this article, the photochemical reaction of xanthone in alcohol was studied by a time-resolved ESR technique, and the CIDEP spectra of the transient radicals peculiarly reveal...
Abstract: The hydrochloric-acid-addition effect on the photochemical reaction of xanthone in alcohol is studied by a time-resolved ESR technique. The CIDEP spectra of the transient radicals peculiarly reveal...

Journal ArticleDOI
TL;DR: The replacement of H2O by D2O as solvent leads to a significant decrease in the equilibrium constant for complexation of excited triplet xanthone with β-cyclodextrin this article.
Abstract: The replacement of H2O by D2O as solvent leads to a significant decrease in the equilibrium constant for complexation of excited triplet xanthone with β-cyclodextrin, mainly as the result of the decrease in the corresponding association rate constant.

Journal ArticleDOI
TL;DR: A new, highly prenylated xanthone, gracilixanthone (1), was isolated from Calophyllum gracilips together with three other known xanthones, pyranojacareubin (2), caloxanthone C (3) and trapezifolixanthones (4) as mentioned in this paper.
Abstract: A new, highly prenylated xanthone, gracilixanthone (1), was isolated from Calophyllum gracilipes together with three other known xanthones, pyranojacareubin (2), caloxanthone C (3) and trapezifolixanthone (4).

Journal ArticleDOI
TL;DR: A route to benzophenones based on a multistep construction of a cationic xanthone iron complex followed by nucleophilic ring-opening and a new, one-pot cyanide addition-decomplexation procedure is described in this paper.

Journal Article
Mao Sl1, Liao Sx, Wu Jh, Ling N, Chen H, Liang Hq, Liu Mz 
TL;DR: Two new compounds were isolated from the roots of Polygala arillata Buch-Ham and pharmacological study indicated that I and II have inhibitory effect on aldose reductase activity.
Abstract: Two new compounds were isolated from the roots of Polygala arillata Buch Ham.. On the basis of chemical reactions and spectral (UV, IR, MS, 1HNMR, DIFNOE, 13 CNMR) analysis,they were identified as 1,3 dihydroxy 2 methoxyxanthone(I) and 7 hydroxy 1 methoxy 2,3 methylenedioxyxanthone(II). Pharmacological study indicated that I and II have inhibitory effect on aldose reductase activity.

Journal ArticleDOI
TL;DR: In this article, a new xanthone (2,7dihydroxyxanthone) was isolated from the aerial parts (stems and bark) of Mammea acuminata.
Abstract: From the stem of Poeciloneuron pauciflorum , two new xanthones (1,6-dihydroxy-7-methoxyxanthone and 1,6-dihydroxy-7-methoxyxanthone 6-O-β- d -glucoside ) in addition to 12 known compounds (1,5-dihydroxy-, 1,5-dihydroxy-3-methoxy-, 1,7-dihydroxy-, 1-hydroxy-7-methoxy-, 2-methoxy-, 4-methoxy-, 1,4,5-trihydroxy-, 1,3,5-trihydroxy-, 1,3,6-trihydroxy-7-methoxy-, 1,3,7-trihydroxy-, 3-hydroxy-2-methoxyxanthone and (−)-epicatechin) were isolated. From the aerial parts (stems and bark) of Mammea acuminata , a new xanthone (2,7-dihydroxyxanthone) was isolated in addition to two known xanthones (1,5-dihydroxy- and 5-hydroxy-1-methoxyxanthone) and (−)-epicatechin. The structures were established by spectral analysis and total synthesis in case of 1,6-dihydroxy-7-methoxyxanthone.

Journal ArticleDOI
TL;DR: In this paper, the 1H-and 13C-NMR spectral data of 1,6-dihydroxy-5-(3-methylbut-2-enyl)-6',6'-dimethyl-pyrano(2',3';7,8)-6",6"-dimethylpolyphenol(2",3";3,2) xanthone and 1,3-6-trihydroxy-6',6',dimethyl polyphenol (2',3,6)-pirano (2,3,3
Abstract: The 1H-and 13C-NMR spectral data of 1,6-dihydroxy-5-(3-methylbut-2-enyl)-6’,6’-dimethyl-pyrano(2’,3’;7,8)-6",6"-dimethyl-pyrano(2",3";3,2) xanthone and 1,3,6-trihydroxy-6’,6’-dimethyl-pirano(2’,3’;7,8)-2,5-di-(3-methylbut-2-enyl)xanthone have been unambiguously assigned by the analysis of homonuclear (1H-1H-COSY) and heteronuclear [1H-13C-COSY: modulated with 1JCH and nJCH (n = 2 and 3, COLOC)] shift-correlated and NOE difference spectra.

Journal ArticleDOI
TL;DR: Among the new derivatives, the 3,6‐diisopropoxyxanthone (2a) has shown significant bone resorption inhibition in in vitro and in vivo tests.
Abstract: A topological modification of ipriflavone 1, a recent antiosteoporotic drug, is described. The flavone moiety of 1 has been replaced by a xanthone one. Among the new derivatives, the 3,6-diisopropoxyxanthone (2a) has shown significant bone resorption inhibition in in vitro and in vivo tests.

Journal Article
TL;DR: A series of appropriate aminoalkanolic derivatives of xanthone III-VIII was synthesized and evaluated as potential antiarrhythmic agents and tested for the effect on the cardiovascular system.
Abstract: A series of appropriate aminoalkanolic derivatives of xanthone III-VIII was synthesized and evaluated as potential antiarrhythmic agents. They were also tested for the effect on the cardiovascular system. The structure of the synthesized compounds was verified by IR 1H NMR, 13C NMR and mass spectral data.


Journal ArticleDOI
TL;DR: In this article, the chemical constituents of the roots of Garcinia dulcis are investigated and three new benzophenone-xanthone dimers named garciduols A-C (1-3) are identified.
Abstract: Investigation of the chemical constituents of the roots of Garcinia dulcis resulted in the isolation of three new benzophenone-xanthone dimers named garciduols A-C (1-3) in addition to a new xanthone, 1,3,6-trihydroxy-7-methoxyxanthone (4). Five known xanthones [2,5-dihydroxy-1-methoxy- (5), 1,4,5-trihydroxy- (6), 1,3,5-trihydroxy-(7), 1,3,6-trihydroxy-5-methoxy- (8) and 1,3,6-trihydroxy-8-isoprenyl-7-methoxyxanthone (9)] were also isolated from the roots. Their structures were determined by spectroscopic analysis including two dimensional NMR. The behaviors of chemical shifts caused by acetylation and the position of the methoxyl group in the dimers characterized by model synthetic benzophenones are also discussed.

Journal ArticleDOI
TL;DR: In this paper, a new polyoxygenated xanthone mangostanol was isolated from the fruit hull of Garcinia mangostana, along with known xanthones, α-mangostin, γ-mengostin and gartanin, 8-deoxygartnin, 5,9-dihydroxy-2,2-dimethyl-8-methoxy-7-(3-methylbut-2-enyl)-2 H,6 H -pyrano[3, 2-b ]xanthen
Abstract: During studies for identification of biologically active components from natural sources, a new polyoxygenated xanthone mangostanol was isolated from the fruit hull of Garcinia mangostana , along with known xanthones, α-mangostin, γ-mangostin, gartanin, 8-deoxygartnin, 5,9-dihydroxy-2,2-dimethyl-8-methoxy-7-(3-methylbut-2-enyl)-2 H ,6 H -pyrano[3,2- b ]xanthen-6-one, garcinone E and 2-(γ,γ-dimethylallyl)-1,7-dihydroxy-3-methoxyxanthone and epicatechin. Spectroscopic analysis mainly by 1D and 2D NMR spectroscopy, established the structure of mangostanol {3,5,9-trihydroxy-2,2-dimethyl-8-methoxy-7-(3-methylbut-2-enyl)-2 H ,6 H -3,4-dihydropyrano[3,2- b ]xanthen-6-one} Mangostanol, and α- and γ-mangostin show moderate inhibitory effects on cAMP phosphodiesterase.

Journal ArticleDOI
TL;DR: A series of xanthone-1,4-dihydrophyridine derivatives bearing a chlorine atom in the xanthon nucleus was prepared and showed selectivity for cardiac vs. vascular tissues improving to some extent selectivity.
Abstract: A series of xanthone-1,4-dihydrophyridine derivatives bearing a chlorine atom in the xanthone nucleus was prepared. The compounds were evaluated for inotropic, chronotropic and calcium antagonist properties. The chlorine introduction in the xanthone moiety slightly affected affinity for cardiac vs. vascular tissues improving to some extent selectivity.

Journal ArticleDOI
TL;DR: In this paper, reaction of dienamine with dimethyl acetylenedicarboxylate and dimethyl maleimide was shown to yield xanthone and chromone, respectively.
Abstract: Reaction of dienamine 2 (R = H and Me) with N -phenylmaleimide or chromone 3 gives xanthones 5 and 8, respectively, through initial [4 + 2] cycloaddition, whereas reaction with dimethyl acetylenedicarboxylate affords xanthone 13.